It is well known to apply ultraviolet curable coating to various types of object and to expose the same to ultraviolet radiation to produce a cured coating with desirable properties. For some curing chemistries, the presence of oxygen tends to inhibit the curing process, and so for such chemistries the amount of oxygen must be controlled. A common way of accomplishing this is to provide a curing chamber in which a flow of nitrogen is used to displace the oxygen so that an inert atmosphere is provided.
A curing chamber is a relatively large and expensive structure, costing in the order of $150,000. The inert gas is introduced into the chamber by a variety of nozzles which are typically permanently secured to the chamber framework. When an improvement occurs in the nozzle technology, a brand new curing chamber would have to be built to incorporate the improvement, making the existing one obsolete. There is, therefore, a need for a curing chamber where the nozzles are removably secured to the chamber structure so that when improvement occurs in the nozzle technology, the existing chamber can be retrofitted with the new nozzles.
Prior art curing chambers are typically built for specific applications, such as using a specific ultraviolet processor for curing a product traversing through the chamber at a specific speed. If the user desires to increase the curing speed to cure more products per given time, the existing curing chamber may not be adequate, since the nozzles built into the machine may not be adequate to maintain the required inert atmosphere at the higher speed. In this case, the user would either deliver increased amount of nitrogen into the chamber to compensate for the increased speed or invest in a new curing chamber, requiring additional investments and space. Increasing the amount of nitrogen delivered to the curing chamber to accommodate the new application is relatively expensive, since nitrogen is an expensive commodity. There is, therefore, a need for a curing chamber where the nozzles can be changed or adjusted without replacing the entire curing chamber to accommodate the user's new application, without increasing nitrogen consumption or purchasing a new curing chamber.